Types of Mold: What Homeowners Need to Know


This post may contain affiliate links. When you buy through some links on this post, we may earn an affiliate commission.

Mold growth in the home can be a serious problem, and understanding types of mold is an important step for homeowners to take when assessing any potential water damage or black mold issue. Types of mold vary greatly, from nearly harmless mildew to the most dangerous forms such as stachybotrys chartarum – also known as ‘black toxic mold'.

Knowing what type of fungus has grown in your home will help you determine how severe the situation is and whether professional remediation services are necessary.

In this blog post we'll explore different kinds of molds, their causes, signs that they have taken hold in your house, health risks associated with them, and ultimately why engaging professional assistance may be the best way forward if you find yourself dealing with an infestation.

Types of Mold

Mold is a type of fungus that can be found both indoors and outdoors. It grows in moist, damp environments and reproduces by releasing tiny spores into the air. Mold can cause health problems if left untreated, so it’s important to understand the different types of mold and how they affect your home.

Allergenic Molds

Allergenic molds are common household molds that produce allergens that can trigger allergic reactions such as sneezing, coughing, wheezing, watery eyes or skin irritation in people who are sensitive to them.

Mold species that can cause allergies are not necessarily toxic otherwise, and toxic species will not always cause allergic symptoms in everyone. A good example of this is the Aspergillus genus of mold; some are toxic, while others may only cause allergic symptoms.

Examples of allergenic molds:

  • Alternaria alternate
  • Aspergillus genus
  • Cladosporium herbarum
  • Penicillium genus

Pathogenic Molds

Pathogenic molds produce toxins known as mycotoxins, which can cause serious illnesses in humans when inhaled or ingested over long periods. These molds typically grow on food sources like fruits and vegetables but can also grow inside homes with high humidity or poor ventilation systems.

Examples include Stachybotrys chartarum (black mold) and Fusarium species.

Examples of pathogenic molds:

  • Aspergillus fumigatus
  • Aspergillus flavus
  • Aspergillus niger
  • Aspergillus versicolor
  • Cryptococcus neoformans
  • Histoplasma capsulatum

Toxigenic Molds

Toxigenic molds release toxins called volatile organic compounds (VOCs) into the air, which may irritate the respiratory system when breathed in for extended periods, leading to symptoms such as headaches, nausea, or dizziness, among others, depending on individual sensitivity levels.

Common examples include Penicillium and Aspergillus species.

Examples of toxigenic molds:

  • Fusarium solani
  • Fusarium moniliform
  • Fusarium oxysporum
  • Penicillium species, including P. brevicompactum, P. citrinum, P. spinulosum, and more
  • Aspergillus species, including A. niger, A. flavus, and A. versicolor
  • Stachybotrys species, including S. chartarum, S. alternans, and all other species

Causes of Mold Growth

Understanding the causes of mold growth can help homeowners take preventative measures to reduce their risk.

High Humidity Levels

High humidity is one of the most common causes of mold growth in homes. When relative humidity levels exceed 60%, it creates an environment where mold spores can easily grow and spread. Keeping indoor humidity levels below 50% is important to reduce the risk.

This can be done using dehumidifiers and air conditioners when necessary. Digital hygrometers are fairly cheap and can monitor your home's humidity level. If it goes above 50%, you need to do something about it.

Poor Ventilation

Poor ventilation also contributes to high indoor humidity levels, increasing mold growth chances. Without proper airflow, moisture from showers, cooking, and other activities will remain trapped inside your home, creating an ideal environment for mold spores to thrive. Installing exhaust fans near bathrooms and kitchens is essential for reducing moisture buildup and preventing potential problems with mold growth.

If you can't install an exhaust fan in the bathroom or kitchen, opening windows or doors can help with ventilation issues when it's reasonable.

Leaking pipes or roofs

These are another major cause of water damage that often leads to black mold infestations in homes and commercial buildings. It is important to check your roof regularly for any signs of leaks such as discoloration on walls or ceilings, and inspect all plumbing fixtures throughout your home for any visible signs of leaking pipes or fittings that could lead to water damage issues over time if left unchecked.

You should also check the following:

  • Under sinks
  • Toilet wax rings
  • Washing machine water hookups
  • Dishwashers
  • Water heaters
  • Utility sinks
  • Roof vents

Signs of Mold Growth in the Home

It is important to recognize the signs of mold growth so that it can be addressed quickly and effectively.

Visible Spots or Discoloration on Walls and Ceilings

One of the home's most common signs of mold growth is visible spots or discoloration on walls and ceilings. These spots may appear as black, green, yellow, white, or gray patches that are often fuzzy or slimy in texture. They may also have an unpleasant, musty odor, leading to our next section.

Musty Odors in the Home

Musty odors are another sign of potential mold growth in your home. Musty smells aren't only caused by mold, but if you have this odor in your home, it's likely due to stagnant air and if you don't already have mold, you will if you don't do something about it.

If you have a significant amount of mold in your home, the smell can permeate throughout.  The musty odor could indicate water damage behind the walls, which has allowed mold to grow undetected for some time.

Water Stains on Walls and Floors

Water stains indicate that you may have a problem with hidden moisture, which can lead to mold growth over time if left unchecked. Suppose you notice any unexplained water stains appearing on your walls or floors.

In that case, this could indicate that you need to investigate further for possible sources of moisture, such as leaking pipes or roofs leaks, before they cause more serious problems down the line, like black mold infestations.

Suppose you suspect any water damage or see signs of potential hidden moisture issues such as visible spots, musty odors, or water stains. In that case, contacting a professional water damage company is best immediately. They can assess the situation properly and take appropriate action before things worsen.

Health Risks Associated with Mold Exposure

Mold exposure can harm your health, and it is important to understand its risks.

Respiratory Issues

Mold spores can cause respiratory issues such as coughing, wheezing, and asthma attacks. People with allergies or asthma may experience more severe symptoms when exposed to mold. If you are experiencing any of these symptoms after mold exposure, seek medical attention immediately.

Skin Irritation and Allergic Reactions

Mold exposure can also lead to skin irritation and allergic reactions such as itching, redness, and swelling. In some cases, people may develop a rash or hives if they come into contact with certain molds. It is important to avoid touching any visible mold growth to prevent these reactions from occurring.

Eye irritation

This is another common symptom of mold exposure that includes burning sensations, watery eyes, and blurred vision. This type of eye irritation should not be ignored since it could indicate an underlying infection caused by mold spores in the air.

Suppose you are experiencing this type of eye irritation after being exposed to mold for an extended period. In that case, it is important to consult a doctor immediately for proper diagnosis and treatment options available to relieve your symptoms.

Mold exposure can cause various health problems, so it's important to identify and address the source of moisture as soon as possible. Professional mold remediation services can help protect your family from further harm by inspecting for sources of moisture, removing contaminated materials, and cleaning and sanitizing affected areas.

Professional Mold Remediation Services

Mold remediation identifies, removes, and cleans up mold growth in homes. Professional mold remediation services are necessary to ensure that the affected areas are properly treated and all potential sources of moisture have been identified and addressed.

Inspection to Identify Sources of Moisture and Contaminated Areas

The first step in any professional mold remediation service is an inspection. This includes checking for visible signs of water damage or black mold growth such as discoloration on walls or ceilings, musty odors, or water stains on floors or walls. Additionally, inspectors will look for hidden sources of moisture, such as leaking pipes or roofs, which can lead to future problems with mold growth if not addressed quickly.

Removal of Contaminated Materials

Once the source(s) of moisture has been identified and addressed, any materials that the presence of black mold has contaminated must be removed from the home. Depending on where the contamination has occurred, this may include drywall, insulation, carpets/rugs, furniture pieces, etc. All items should be disposed of safely according to local regulations so as not to spread further contamination.

After removing all contaminated materials from your home, the professional will clean and sanitize affected areas. Specialized equipment, like permanent filtration systems with negative air systems, can remove particles down to 0.3 microns in size, including spores. Additionally, antimicrobial solutions help kill remaining traces of mold and bacteria while preventing future outbreaks from occurring again in the home environment once everything has dried out.


Professional mold remediation services are available to help homeowners address water damage and black mold issues in their homes. It is important to take action quickly when dealing with water damage or mold so that further damage does not occur.

By understanding different types of molds and seeking professional assistance when needed, homeowners can protect their family’s health and their property from further harm caused by water damage or black mold.

Are you dealing with mold in your home or business? Don't wait for the problem to get worse. Damage Control 911 is here to help! We are a water damage restoration and mold remediation contractor located in Orlando, Florida, specializing in removing all types of mold from any environment. Our team has years of experience working on residential and commercial properties throughout Central Florida. We can provide solutions tailored specifically to your needs. Contact us today, and let us take care of the problem before it gets out of hand!

Recent Posts